A novel technique to cover microfluidic systems with Parylene-C

This paper describes a novel technique for covering microfluidic systems using Parylene-C. Microfluidic systems consisting of micro channels and reservoirs need to be covered to protect or isolate liquid samples from the environment. Thick photoresist and wax are employed as the sacrificial layers in the enclosed micro channels and reservoirs before Parylene-C sealing. The results show that the melted wax improves adherence on a flat and neat Parylene-C film cover and can greatly benefit the mass production. After removing the sacrificial layers, Parylene-C is heated to 120°C to change the residual stress of Parylene-C film to strongly tensile for a flatter surface.